Technical Abstract:
Rice is a good source of readily digestible starch and protein, which are important to humans for energy or as a source of amino acids. Rice's concentration of vitamins, minerals, and health-promoting phytochemicals, however, is quite low, especially when one assesses the polished grain. These nutrient limitations are not a major concern for consumers in developed countries, where rice is eaten in a mixed diet; however, it is a major concern in developing countries where rice is a staple food, and might contribute 50-70% of daily caloric intake in some populations. To enhance the nutritional value of rice, researchers have designed several genetic engineering strategies to manipulate the expression of diverse biosynthetic pathways in the developing rice grain. Sufficient molecular information is now available to alter carotenoids (especially pro-vitamin A), tocopherols and tocotrienols (vitamin E), folate, and even amino acid or protein levels. Similarly, there are strategies available to enhance the mineral composition of rice through alterations at the grain and/or whole-plant levels. In this presentation, we will focus our discussion on Golden Rice, the transgenic product that produces beta-carotene in the grains, as an example for other genetic engineering strategies. We will discuss how efforts are already underway to combine more nutritional traits onto a Golden Rice platform. We will provide an overview of the range of nutritional strategies that are possible for rice, the impact these changes might have on the farmer, and the challenges/benefits these might pose to the processor. Lastly, we will discuss the dietary impact of these nutritional changes for the consumer and the potential opportunities for those who market rice products.